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  • 1.
    Bitaraf Haghighi, Ehsan
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Saleemi, Mohsin
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Behi, Mohammadreza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Mirmohammadi, Seyed Aliakbar
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Poth, H.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Toprak, Muhammet S.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Palm, Björn
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Shelf stability of nanofluids and its effect on thermal conductivity and viscosity2013In: Measurement science and technology, ISSN 0957-0233, E-ISSN 1361-6501, Vol. 24, no 10, p. 105301-Article in journal (Refereed)
    Abstract [en]

    This study proposes a method and apparatus to estimate shelf stability of nanofluids. Nanofluids are fabricated by dispersion of solid nanoparticles in base fluids, and shelf stability is a key issue for many practical applications of these fluids. In this study, shelf stability is evaluated by measuring the weight of settled solid particles on a suspended tray in a colloid versus time and correlated with the performance change of some nanofluid systems. The effects of solid particle concentration and bath sonication time were investigated for selected nanofluids. The results show the applicability of this simple method and the apparatus to evaluate nanofluid shelf stability. Furthermore, it shows that Stokes' law is not valid for determining the settling time of the tested nanoparticles probably due to their complicated shape and presence of surface modifiers. The effect of shelf stability on thermal conductivity and viscosity was illustrated for some nanofluids. Experimental results show that water-based Al2O3 nanofluids have quite good shelf stability and can be good candidates for industrial applications.

  • 2.
    Bitaraf Haghighi, Ehsan
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Saleemi, Mohsin
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Anwar, Zahid
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Lumbreras, Itziar
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Behi, Mohammadreza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Mirmohammadi, Seyed A.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Poth, Heiko
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Toprak, Muhammet S.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Palm, Björn
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Cooling performance of nanofluids in a small diameter tube2013In: Experimental Thermal and Fluid Science, ISSN 0894-1777, E-ISSN 1879-2286, Vol. 49, p. 114-122Article in journal (Refereed)
    Abstract [en]

    This article reports convective single-phase heat transfer performance in laminar flow for some selected nanofluids (NFs) in an open small diameter test section. A 0.50 mm inner diameter, 30 cm long stainless steel test section was used for screening single phase laminar convective heat transfer with water and five different water based NFs. Tested NFs were; Al2O3 (two types), TiO2 (two types) and CeO2 (one type), all 9 wt.% particle concentration. The effective thermal conductivity of the NFs were measured with Transient Plane Source (TPS) method and viscosity were measured with a rotating coaxial cylindrical viscometer. The obtained experimental results for thermal conductivity were in good agreement with the predicted values from Maxwell equation. The local Shah correlation, which is conventionally used for predicting convective heat transfer in laminar flow in Newtonian fluids with constant heat flux boundary condition, was shown to be valid for NFs. Moreover, the Darcy correlation was used to predict the friction factor for the NFs as well as for water. Enhancement in heat transfer for NFs was observed, when compared at equal Reynolds number, as a result of higher velocity or mass flow rate of the NFs at any given Reynolds number due to higher viscosity for NFs. However, when compared at equal pumping power no or only minor enhancement was observed.

  • 3.
    Bitaraf Haghighi, Ehsan
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Saleemi, Mohsin
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Ghadamgahi, Mersedeh
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Palm, Björn E.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Toprak, Muhammet
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Measurement of temperature–dependent viscosity of nanofluids and its effect on pumping power in cooling systems2013Conference paper (Refereed)
    Abstract [en]

    Nanofluids are engineered colloids of nanoparticlesdispersed homogenously in a base fluid, which theirthermophysical properties are changed by adding solidnanoparticles. Among the characteristic parameters,viscosity is one of the most important, as it directly affectsthe pumping power in cooling systems. In this study, theviscosity of water based Al2O3, ZrO2, and TiO2 (with 9wt%for all) nanofluids was measured and its impact on pressuredrop in a simple tubular pipe was estimated for bothlaminar and turbulent flow by classical correlations. Theeffect of temperature on the viscosity of these nanofluidswas also studied in the temperature range of 5˚C - 30˚C. Toassess the applicability of the classical correlations, pressuredrops across an open 30cm long, 0.50mm diameterstainless steel test section was measured for water andnanofluids by a differential pressure transducer. Theaverage viscosity increments compared to water in thetemperature range of 5˚C - 30˚C are 105%, 98% and 31% forAl2O3, ZrO2, and TiO2 nanofluids respectively. Moreover, theresults show that the viscosity of nanofluids decreases withthe increase of temperature; however the relative viscosity,which is defined as the viscosity ratio between a nanofluidand its base fluid is constant in 5˚C - 30˚C temperaturerange.

  • 4.
    Ghanbarpour, Morteza
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Nikkam, N.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Toprak, Muhammet S.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Improvement of heat transfer characteristics of cylindrical heat pipe by using SiC nanofluids2015In: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606, Vol. 90, p. 127-135Article in journal (Refereed)
    Abstract [en]

    An experimental study was performed to investigate the thermal performance of heat pipes using SiC/water nanofluid as the working fluid. Four cylindrical copper heat pipes containing two layers of screen mesh were fabricated and tested with water and water based SiC nanofluids with nanoparticle mass concentrations of 0.35%, 0.7% and 1.0% as working fluids. SiC nanofluids properties and characteristics are evaluated and its effects on thermal performance improvement of screen mesh heat pipes at different concentrations and inclination angles are investigated. Experimental results show that nanofluid improves the performance of the heat pipes and the thermal resistance of the heat pipe with SiC nanofluid decreases with increasing nanoparticle concentration. Thermal resistance reduction of heat pipes by 11%, 21% and 30% was observed with SiC nanofluids containing 0.35 wt.%, 0.7 wt.% and 1.0 wt.% SiC nanoparticles as compared with water. In addition, it is revealed that the inclination angle has remarkable influence on the thermal performance of the heat pipes and the lowest thermal resistance belongs to the inclination angle of 60 in all concentrations. The present investigation indicates that the maximum heat removal capacity of the heat pipe increases by 29% with SiC nanofluids at nanoparticle mass concentration of 1.0 wt.%.

  • 5.
    Ghanbarpour, Morteza
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Experimental study of nanofluid effect on thermal performance of screen mesh heat pipe2013Conference paper (Refereed)
  • 6.
    Ghanbarpour, Morteza
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Toprak, Muhammet
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics.
    Thermal performance of inclined screen mesh heat pipes using silver nanofluids2015In: International Communications in Heat and Mass Transfer, ISSN 0735-1933, E-ISSN 1879-0178, Vol. 67, p. 14-20Article in journal (Refereed)
  • 7.
    Haghighi, Ehsan Bitaraf
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Saleemi, Mohsin
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Toprak, Muhammet S.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Palm, Björn
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Accurate basis of comparison for convective heat transfer in nanofluids2014In: International Communications in Heat and Mass Transfer, ISSN 0735-1933, E-ISSN 1879-0178, Vol. 52, p. 1-7Article in journal (Refereed)
    Abstract [en]

    Thermal conductivity and viscosity of alumina (Al2O3), zirconia (ZrO2), and titania (TiO2) nanofluids (NFs) were measured at 20°C. All the NF systems were water based and contained 9wt.% solid particles. Additionally, the heat transfer coefficients for these NFs were measured in a straight tube of 1.5m length and 3.7mm inner diameter. Based on the results, it can be stated that classical correlations, such as Shah and Gnielinski, for laminar and turbulent flow respectively, can be employed to predict convective heat transfer coefficients in NFs, if the accurate thermophysical properties are used in the calculations. Convective heat transfer coefficients for NFs were also compared with those of the base fluids using two different bases for the comparison, with contradictory results: while compared at equal Reynolds number, the heat transfer coefficients increased by 8-51%, whereas compared at equal pumping power the heat transfer coefficients decreased by 17-63%. As NFs have higher viscosity than the base fluids, equal Reynolds number requires higher volumetric flow, hence higher pumping power for the NFs. It is therefore strongly suggested that heat transfer results should be compared at equal pumping power and not at equal Reynolds number.

  • 8.
    Jarahnejad, Mariam
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Haghighi, Ehsan B.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Saleemi, Mohsin
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Palm, Björn
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Toprak, Muhammet S.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Experimental investigation on viscosity of water-based Al2O3 and TiO2 nanofluids2015In: Rheologica Acta, ISSN 0035-4511, E-ISSN 1435-1528, Vol. 54, no 5, p. 411-422Article in journal (Refereed)
    Abstract [en]

    This article investigates the influence of temperature, concentration, and size of nanoparticles, and addition of surfactants on dynamic viscosity of water-based nanofluids containing alumina (Al2O3) and titania (TiO2) nanoparticles. Two viscometers, a capillary and a falling ball, were used for the measurements in the temperature range of 20-50 A degrees C and the particle concentration of 3-14.3 wt.%. The results indicate that the viscosity of nanofluids is reduced by increasing the temperature, similar to their base fluids. Moreover, surfactants, which are used to improve the shelf stability of nanofluids, most likely increase their viscosity. The correlations derived from the linear fluid theory such as Einstein and Batchelor, especially for solid concentration above 1.5 wt.% are not accurate to predict viscosity of nanofluids, while the modified Krieger-Dougherty equation estimates viscosity of nanofluids with acceptable accuracy in a specific range of solid particle size to aggregate size.

  • 9. Krajnik, P.
    et al.
    Muhammed, M.
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Rashid, A.
    Toprak, Muhammet
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Heat exchange fluid comprising layered structured particles in a base liquid, method of preparation thereof and its application: Värmeväxlarvätskan innehållande skikt-strukturerade partiklar i en basvätska, metod för framställning därav och dess tillämpning2012Patent (Other (popular science, discussion, etc.))
  • 10.
    Krajnik, Peter
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Rashid, Amir
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering.
    Pusavec, Franci
    Remskar, Maja
    Yui, Akinori
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics.
    Toprak, Muhammet S.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics.
    Transitioning to sustainable production - part III: developments and possibilities for integration of nanotechnology into material processing technologies2016In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 112, p. 1156-1164Article in journal (Refereed)
    Abstract [en]

    A nanoparticle-based cooling-lubricating fluid (nCLF), designed and fabricated by suspending engineered nanoparticles (ENPs) in biodegradable vegetable-based fluids, has been developed for integration into material processing technologies. This new product exhibits tribological properties superior to those of conventional metalworking fluids. The major innovation is the ability to create a stable nCLF through the modification of ENP surfaces. Functionalized MoS2 nanotube ENPs were successful used as low friction additives. The experimental work, required for the proof-of-concept and technology validation, was carried out on three different levels to quantify the improved tribological behavior of nCLF. These experiments include standard tribological tests, mock-up tests to simulate machining, and actual machining tests. It is demonstrated that the specific properties of ENPs, fluid design and composition, as well as specific lubrication mechanisms, exhibit superior performance of nCLF in terms of friction and wear. The objective of this paper is to demonstrate how recent nanotechnology developments support innovation needed for transitioning to sustainable production via new product development and integrated industrial applications.

  • 11.
    Morteza, Ghanbarpourgeravi
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Nader, Nikkam
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Toprak, Mohammet S
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics.
    Muhammed, Mamoun Ali
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics.
    Thermal performance of screen mesh heat pipe with Al2O3 nanofluid2015In: Experimental Thermal and Fluid Science, ISSN 0894-1777, E-ISSN 1879-2286, Vol. 66, p. 213-220Article in journal (Refereed)
    Abstract [en]

    This study presents the effect of Al2O3 nanofluid (NF) on thermal performance of screen mesh heat pipe in cooling applications. Three cylindrical copper heat pipes of 200 mm length and 6.35 mm outer diameter containing two layers of screen mesh were fabricated and tested with distilled water and water based Al2O3 NF with mass concentrations of 5% and 10% as working fluids. To study the effect of NF on the heat pipes thermal performance, the heat input is increased and then decreased consecutively and the heat pipes surface temperatures are measured at steady state conditions. Results show that using 5 wt.% of Al2O3 NF improves the thermal performance of the heat pipe for increasing and decreasing heat fluxes compared with distilled water, while utilizing 10 wt.% of Al2O3 NF deteriorates the heat pipe thermal performance. For heat pipe with 5 wt.% Al2O3 NF the reduction in thermal resistance of the heat pipe is found to be between 6% and 24% for increasing and between 20% and 55% for decreasing heat fluxes, while the thermal resistance increased between 187% and 206% for increasing and between 155% and 175% for decreasing steps in heat pipe with 10 wt.% of Al2O3 NF.

  • 12.
    Motahar, Sadegh
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology. Department of Mechanical Engineering, Isfahan University of Technology, Iran.
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Alemrajabi, Ali A.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Toprak, Muhammet S.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    A novel phase change material containing mesoporous silica nanoparticles for thermal storage: A study on thermal conductivity and viscosity2014In: International Communications in Heat and Mass Transfer, ISSN 0735-1933, E-ISSN 1879-0178, Vol. 56, p. 114-120Article in journal (Refereed)
    Abstract [en]

    In this research, mesoporous silica (MPSiO2) nanoparticles were dispersed in n-octadecane as an organic phase change material (PCM) in order to produce a novel composite for thermal storage. Stable PCMs containing 1 wt.%, 3 wt.% and 5 wt.% MPSiO2 nanopartides (PCM/MPSiO2) were fabricated by dispersing MPSiO2 in PCM. MPSiO2 particles were investigated by SEM and TEM techniques, which showed high order of porosity and spherical particles of ca. 300 nm. The thermal conductivity in both solid and liquid phases was measured by transient plane source (TPS) technique in the temperature range of 5-55 degrees C. A maximum thermal conductivity enhancement of 5% for 3 wt.% MPSiO2 at 5 degrees C, and 6% for 5 wt.% MPSiO2 at 55 degrees C was experimentally obtained. Moreover, it was observed that enhancement in thermal conductivity is non-monotonic in solid phase with increasing MPSiO2 particle loading. The viscosity results showed that for mass fractions of nanoparticles greater than 3% in liquid PCM, the behavior of liquid is non-Newtonian. Also, the viscosity of PCM containing MPSiO2 nanopartides was measured to be increased up to 60% compared to the liquid PCM for 5 wt% MPSiO2 at 35 degrees C.

  • 13. Motahar, Sadegh
    et al.
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Alemrajabi, Ali A.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Toprak, Muhammet S.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics.
    Experimental investigation on thermal and rheological properties of n-octadecane with dispersed TiO2 nanoparticles2014In: International Communications in Heat and Mass Transfer, ISSN 0735-1933, E-ISSN 1879-0178, Vol. 59, p. 68-74Article in journal (Refereed)
    Abstract [en]

    In the present study, titanium (IV) oxide (TiO2) nanoparticles were dispersed in n-octadecane to fabricate phase change material (PCM) with enhanced properties and behavior. Thermal conductivity (TC) and viscosity of n-octadecane/TiO2 dispersions were experimentally investigated using transient plane source (TPS) technique and rotating coaxial cylindrical viscometer, respectively. The results showed that the TC of n-octadecane/TiO2 dispersion depends on temperature and nanoparticle loading. A non-monotonic behavior of TC enhancement in both solid and liquid phases was observed. In solid phase, the maximum TC enhancement occurred at 3 wt.% of nanoparticles. When the nanoparticle mass fraction was over 4% in liquid phase, the TC started to decrease. The rheological behavior of the n-octadecane/TiO2 samples indicated that dispersions with low nanoparticle mass fractions demonstrate Newtonian behavior, and for higher mass factions the shear-thinning behavior was observed. Shear stress vs. shear rate curves showed that the liquid phase of PCM behaves like a Bingham plastic fluid for mass fraction greater than 1%. As expected, the effective viscosity could be influenced by temperature. At the shear rate of 48.92 s(-1) for 3 wt.% nanoparticles, the effective viscosity decreased by 26.8% while temperature increased from 35 degrees C to 55 degrees C. For the investigated n-octadecane/TiO2 dispersions, new thermophysical correlations are proposed for predicting TC and rheological properties.

  • 14.
    Muhammed, Mamoun
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Toprak, Muhammet
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    The use of a suspension comprising mesoporous silica particles as heat exchange fluids: Användningen av en suspension omfattande mesoporösa kiseldioxidartiklar som värmeväxlarvätska2010Patent (Other (popular science, discussion, etc.))
  • 15.
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Composite Comprising Phase Change Materials Enhanced with Mesoporous Particles for Enhanced Thermal Energy Storage2014Patent (Other (popular science, discussion, etc.))
  • 16.
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Engineering Nanofluids for Heat Transfer Applications2014Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Nanofluids (NFs) are nanotechnology-based colloidal dispersion prepared by dispersing nanoparticles (NPs) in conventional liquids, as the base liquid. These advanced fluids have displayed potential to enhance the performance of conventional heat transfer fluids. This work aims at providing an insight to the field of NFs by investigating in detail the fabrication and evaluation of physico-chemical, thermo-physical and heat transfer characteristics of NFs for practical heat transfer applications. However, in order to utilize NFs as heat transfer fluids in real applications there are some challenges to overcome. Therefore, our goal is not only to optimize the thermo-physical properties of NFs with the highest thermal conductivity (TC) and minimal impact of NPs on viscosity, but also on preparing NFs with good stability and the best heat transfer performance. In the first stage, detailed studies were carried out to engineer NFs with good stability and optimal thermo-physical properties. In this work we investigated the most important factors, and the dependence of thermo-physical properties of NFs, including NP composition and concentration, NF stability, surface modifiers, particle size (NP size and particle with micron size), NF preparation method (two-step vs one-step method) and base liquid was studied. We also demonstrated, for the first time, the role of crystal structure, exemplified by alpha- and beta- SiC particles, on thermo-physical properties of NFs. For these purposes several NFs were fabricated using different nanostructured materials and various base liquids by one-step and two-step methods. An optimization procedure was designed to keep a suitable control in order to reach the ultimate aim where several stages were involved to check the desired characteristics of each NF system. Among several NFs systems studied in the first stage evaluation, a particular NF system with 9 wt% concentration, engineered by dispersing SiC NPs with alpha- crystal structure in water/ethylene glycol as based liquid exhibited the optimal thermo-physical properties. This NF was the only case which could pass the all criteria involved in the optimization procedure by exhibiting good stability, TC enhancements of ~20% with only 14% increase in viscosity at 20 oC. Therefore, this engineered NF was considered for next phase evaluation, where heat transfer coefficient (HTC) tests were designed and carried out to evaluate the thermal transport property of the selected alpha- SiC NF. A HTC enhancement of 5.5% at equal pumping power, as realistic comparison criteria, was obtained indicating the capability of this kind of NFs to be used in industrial heat transfer applications. These findings are among the few studies in the literature where the heat transfer characteristics of the NFs were noticeable, reproducible and based on a realistic situation with capability of commercializing as effective heat transfer fluid.  

  • 17.
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Method and apparatus for simple determination of the stability of suspensions2011Patent (Other (popular science, discussion, etc.))
  • 18.
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Thermal and rheological properties of micro- and nanofluids of copper: designed as heat exchange fluid2013Conference paper (Other academic)
  • 19.
    Nikkam, Nader
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Bitaraf Haghigh, Ehsan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Saleemi, Mohsin
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Behi, Mohammadreza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Palm, Björn
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Toprak, Muhammet S.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Experimental study on preparation and base liquid effect on thermo-physical and heat transport characteristics of α-SiC nanofluids2014In: International Communications in Heat and Mass Transfer, ISSN 0735-1933, E-ISSN 1879-0178, Vol. 55, p. 38-44Article in journal (Refereed)
    Abstract [en]

    Nanostructured solid particles dispersed in a base liquid are a new class of nano-engineeredcolloidal solutions, defined with a coined name of nanofluids (NFs). These fluids have shownpotential to enhance heat transfer characteristics of conventional base liquids utilized in heattransfer application. We recently reported on the fabrication and thermo-physical propertyevaluation of SiC NFs systems, containing SiC particles with different crystal structure. In thisstudy, our aim is to investigate the heat transfer characteristics of a particular α-SiC NF withrespect to the effect of α-SiC particle concentration and different base liquids on the thermophysicalproperties of NFs. For this purpose, a series of NFs with various α-SiC NPsconcentration of 3, 6 and 9wt% were prepared in different base liquids of distilled water (DW)and distilled water/ethylene glycol mixture (DW/EG). Their thermal conductivity (TC) andviscosity were evaluated at 20 oC. NF with DW/EG base liquid and 9wt% SiC NPs loadingexhibited the best combination of thermo-physical properties, which was therefore selected forheat transfer coefficient (HTC) evaluation. Finally, HTC tests were performed and compared indifferent criteria, including equal Reynolds number, equal mass flow rate and equal pumpingpower for a laminar flow regime. The results showed HTC enhancement of NF over the baseliquid for all evaluation criteria; 13% at equal Reynolds number, 8.5% at equal volume flow and5.5% at equal pumping power. Our findings are among the few studies in the literature where theheat transfer enhancement for the NFs over its base liquid is noticeable and based on a realistic situation.

  • 20.
    Nikkam, Nader
    et al.
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Ghanbarpour, Morteza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Khodabandeh, Rahmaatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Toprak, Muhammet S.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Experimental investigation on thermophysical properties of ethylene glycol based copper micro- and nanofluids for heat transfer applications2015In: Materials Research Society Symposium Proceedings, Cambridge University Press, 2015, p. 69-74Conference paper (Refereed)
    Abstract [en]

    The present work reports on the fabrication, experimental and theoretical investigatbn of thermal conductivity (TC) and viscosity of ethylene glycol (EG) based nanofluids/microfluids (NFs/MFs) containing copper nanoparticles (Cu NPs) and copper microparticles (Cu MPs). Cu NPs (20-40 nm) and Cu MPs (0.5-1.5 μm) were dispersed in EG with particle concentration from 1 wt% to 3 wt% using powerful ultrasonic agitation, and to study the real impact of dispersed particles the use of surface modifier was avoided. The objectives were to study the effect of concentration and impact of size of Cu particles on thermo-physical properties, including thermal TC and viscosity, of EG based Cu NFs/MFs. The physicochemical properties of NPs/MPs and NFs/MFs were characterized by using various techniques. The experimental results exhibited higher TC of NFs and MFs than the EG base liquid. Moreover, Cu NFs displayed higher TC than MFs showing their potential for use in some heat transfer applications. Maxwell effective medium theory as well as Einstein law of viscosity was used to compare the experimental data with the predicted values for estimating the TC and viscosity of Cu NFs/MFs, respectively.

  • 21.
    Nikkam, Nader
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Ghanbarpour, Morteza
    Khodabandeh, Rahmattollah
    Toprak, Muhammet S.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Experimental investigation on fabrication and base liquid effect on thermo-physical characteristics of silver nanofluids2015In: Experimental investigation on fabrication and base liquid effect on thermo-physical characteristics of silver nanofluids, 2015Conference paper (Refereed)
    Abstract [en]

    Nanofluids (NFs) are solid-liquid composites prepared by stabilizing nanostructured materials in a base liquid, such as water, ethylene glycol (EG) and engine oil. They have exhibited some potential to replace with conventional heat transfer fluids to enhance their thermal characteristics. NF has complex system and its thermo-physical properties including TC and viscosity can be influenced by several factors such as base liquid. The effect of base liquid on thermo-physical properties of NFs is not well studied. In this work this effect has been studied by comparing the TC and viscosity of a commercial silver (Ag) NFs with lab-made water and EG base Ag NFs. For this purpose, at first commercial water based Ag suspension with 1wt% Ag nanoparticles (NPs) was used. The original suspension was centrifuged and the obtained Ag NPs was re-dispersed in EG to prepare EG based Ag NF (1wt%). In order to study the effect of Ag NP concentration on thermo-physical properties, NFs with various concentrations (1, 1.5 and wt%) were fabricated from the original samples containing 1wt% Ag NP. For this end NFs with higher NP concentrations were fabricated by centrifuging and concentrating these samples in base liquids. Therefore, six NFs with different base liquids (water and EG) and various Ag NP concentrations (1, 1.5 and 2wt%) were prepared and studied. The physicochemical properties of Ag NP/NF were characterized by using various techniques and instruments including Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Electron Diffraction (ED), Dynamic Light Scattering (DLS) and Fourier Transform Infrared Spectroscopy (FT-IR). Ag NP displayed an average primary particle size of 40±5 nm from SEM micrographs. The thermo-physical properties of NFs including TC and viscosity of NFs were measured at different temperatures from 20 to 40 oC. The Newtonian behavior was observed for NFs with both water and EG base liquids. Moreover, viscosity of all NFs was increased by increase of Ag NP concentration and decreased by increase in temperature. The TC of NFs was measured and analyzed by Transient Hot Wire (THW) method at the same temperature range. The TC tests showed increase of TC with the increase of Ag NPs concentration as well as increase in temperature. As a result and compared to the water based suspensions, NFs with EG base liquid revealed higher TC enhancement and lesser viscosity increase. EG based NFs seem to be more beneficial for heat transfer applications. Among all NFs, a maximum TC enhancement of ~12.2 % was obtained for EG based NF with 2wt% Ag NP at 40 oC while maximum increase in viscosity of ~ 4 % was observed for the same NF showing the capability of utilizing this NF as heat transfer fluid. Finally and in order to compare the experimental results with the estimated data, proper predictive models/correlations were applied for NFs with both water and EG base liquids and our finding are presented in detail.

  • 22.
    Nikkam, Nader
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Ghanbarpour, Morteza
    Khodabandeh, Rahmattollah
    Toprak, Muhammet S.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    The effect of particle size on thermo-physical properties of ethylene glycol based copper micro- and nanofluids2015Conference paper (Refereed)
    Abstract [en]

    Nanofluids (NFs), suspension of nanoparticles (NPs) in conventional fluids such as water and ethylene glycol (EG) have been found capable of providing enhanced heat transfer compared to pure heat transfer fluids. Among several factors influencing thermo-physical properties of NFs including thermal conductivity (TC) and viscosity, particle size plays an essential role. Due to limited literature data on the impact of particle size on thermo-physical properties of NFs as well as inconsistent results in the literature, there is a serious need to perform a detailed study on the influence of particle size on thermo-physical properties of NFs. For this purpose a study was carried out using copper nanoparticles (Cu NPs) and copper microparticles (Cu MPs) to investigate, experimentally and theoretically, the effect of Cu NPs and MPs on thermo-physical properties of Cu NFs and Cu microfluids (Cu MFs). A series of stable Cu NFs and MFs with various NP/MP concentration (from1 wt% to 3 wt%) were fabricated by dispersing Cu NPs and Cu MPs in EG. The use of additives/surfactants was avoided to study the real impact of Cu NP/MP. The physico-chemical properties of Cu NFs and MFs were analyzed by various techniques and instruments including Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM) and Dynamic Light Scattering (DLS) and Infrared Spectroscopy (FT-IR). The thermo-physical properties (TC and viscosity) of NFs and MFs were measured at different temperatures between 20 and 40 oC. All Cu NFs and MFs showed higher TC and viscosity compared to the EG base liquid. The viscosity test results showed Newtonian behavior for NFs and MFs. Our study exhibited that NFs with Cu NPs revealed higher TC than those containing Cu MPs at the same particle concentration and temperature. For TC, Maxwell predictive equation and for viscosity of NFs/MFs, Kriger-Dougherty correlation was applied to compare the experimental results with the estimated values. Our findings on the physic-chemical, thermal and thermo-physical properties of the NFs/MFs, containing Cu NPs/MPs are presented in detail.

  • 23.
    Nikkam, Nader
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Ghanbarpour, Morteza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Saleemi, Mohsin
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Haghighi, Ehsan Bitaraf
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Palm, Björn
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Toprak, Muhammet S.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Experimental investigation on thermo-physical properties of copper/diethylene glycol nanofluids fabricated via microwave-assisted route2014In: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606, Vol. 65, no 1-2, p. 158-165Article in journal (Refereed)
    Abstract [en]

    This study investigates the fabrication, thermal conductivity and rheological characteristics evaluation of nanofluids consisting of copper nanoparticles in diethylene glycol base liquid. The fabricated Cu nanofluids displayed enhanced thermal conductivity over the base liquid. Copper nanoparticles were directly formed in diethylene glycol using microwave-assisted heating, which provides uniform heating of reagents and solvent, accelerating the nucleation of metal clusters, resulting in monodispersed nanostructures. Copper nanoparticles displayed an average primary particle size of 75 ± 25 nm from SEM micrographs, yet aggregated to form large spherical particles of about 300 nm. The physicochemical properties including thermal conductivity and viscosity of nanofluids were measured for the nanofluids with nanoparticle concentration between 0.4 wt% and 1.6 in the temperature range of 20-50 C. Proper theoretical correlations/models were applied to compare the experimental results with the estimated values for thermal conductivity and viscosity of nanofluids. For all cases, thermal conductivity enhancement was higher than the increase in viscosity showing the potential of nanofluids to be utilized as coolant in heat transfer applications. A thermal conductivity enhancement of ∼7.2% was obtained for nanofluids with 1.6 wt% nanoparticles while maximum increase in viscosity of ∼5.2% was observed for the same nanofluid.

  • 24.
    Nikkam, Nader
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Ghanbarpour, Morteza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Saleemi, Mohsin
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Toprak, Muhammet S.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Thermal and rheological properties of micro- and nanofluids of copper in diethylene glycol: as heat exchange liquid2013In: Nanoscale Thermoelectric Materials: Thermal and Electrical Transport, and Applications to Solid-state Cooling and Power Generation, Cambridge: Cambridge Scholars Publishing, 2013, , p. 6p. 165-170Conference paper (Refereed)
    Abstract [en]

    This study reports on the fabrication of nanofluids/microfluids (NFs/MFs) with experimental and theoretical investigation of thermal conductivity (TC) and viscosity of diethylene glycol (DEO) base NFs/MFs containing copper nanoparticles (Cu NPs) and copper microparticles (Cu MPs). For this purpose, Cu NPs (20-40 nm) and Cu MPs (0.5-1.5 urn) were dispersed in DEG with particle loading between 1 wt% and 3 wt%. Ultrasonic agitation was used for dispersion and preparation of stable NFs/MFs, and thus the use of surfactants was avoided. The objectives were investigation of impact of size of Cu particle and concentration on TC and viscosity of NFs/MFs on DEG as the model base liquid. The physicochemical properties of all particles and fluids were characterized by using various techniques including Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM) and Dynamic Light Scattering (DLS) techniques. Fourier Transform Infrared Spectroscopy (FTIR) analysis was performed to study particles' surfaces. NFs and MFs exhibited a higher TC than the base liquid, while NFs outperformed MFs showing a potential for their use in heat exchange applications. The TC and viscosity of NFs and MFs were presented, along with a comparison with values from predictive models. While Maxwell model was good at predicting the TC of MFs, it underestimated the TC of NFs, revealing that the model is not directly applicable to the NF systems.

  • 25.
    Nikkam, Nader
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Krajnik, P.
    Rashid, A.
    Muhammed, M.
    Toprak, Muhammet
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Metalworking fluid comprising layered structured particles in a base liquid, method of preparation thereof and its application: Metallbearbetningsvätska innefattande klyvbara nanopartiklar i ett basvätska, metod för framställning därav och dess tillämpning2012Patent (Other (popular science, discussion, etc.))
  • 26.
    Nikkam, Nader
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Saleemi, Mohsin
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Bitaraf Haghighi, Ehsan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Ghanbarpour, Morteza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Toprak, Muhammet
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Palm, Björn
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Design and Fabrication of Efficient Nanofluids Based on SiC Nanoparticles for Heat Exchange Applications2013Conference paper (Other academic)
  • 27.
    Nikkam, Nader
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Saleemi, Mohsin
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Haghighi, Ehsan Bitaraf
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Ghanbarpour, Morteza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Palm, Björn
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Toprak, Muhammet S.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Fabrication, Characterization and Thermo-physical Property Evaluation of SiCNanofluids for Heat Transfer Applications2014In: Nano-Micro Letters, ISSN 2150-5551, Vol. 6, no 2, p. 178-189Article in journal (Refereed)
    Abstract [en]

    Nanofluids (NFs) are nanotechnology-based colloidal suspensions fabricated by suspending nanoparticles (NPs) in a base liquid. These fluids have shown potential to improve the heat transfer properties of conventional heat transfer fluids. In this study we report in detail on the fabrication, characterization and thermo-physical property evaluation of SiC NFs, prepared using SiC NPs with different crystal structure, for heat transfer applications.  For this purpose, a series of SiC NFs containing SiC NPs with different crystal structure (α-SiC and β-SiC) were fabricated in a water (W)/ethylene glycol (EG) mixture (50/50 wt % ratio). Physicochemical properties of NPs/NFs were characterized by using various techniques such as powder X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Fourier Transform Infrared Spectroscopy (FTIR), Dynamic Light Scattering (DLS) and Zeta Potential Analysis were performed. Thermo-physical properties including thermal conductivity (TC) and viscosity for NFs containing SiC particles (α- and β- phase) were measured. The results showed among all suspensions, NF fabricated with α-SiC particles have more favorable thermo-physical properties compared to the NFs fabricated with β-SiC; the observed difference was attributed to combination of several factors, including crystal structure (β- vs. α-), sample purity, and residual chemicals exhibited on SiC nanoparticles. A TC enhancement of ~20% while 14% increased viscosity were obtained for a NF containing 9wt% of particular type of α-SiC NPs indicating promising capability of these kind of NFs for further heat transfer characteristics investigations. 

  • 28.
    Nikkam, Nader
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Saleemi, Mohsin
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Li, S
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Toprak, Muhammet
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Bitaraf Haghighi, Ehsan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Palm, Björn E
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Novel Nanofluids Based on Mesoporous Silica for Enhanced Heat Transfer2011In: Journal of nanoparticle research, ISSN 1388-0764, E-ISSN 1572-896X, Vol. 13, no 11, p. 6201-6206Article in journal (Refereed)
    Abstract [en]

    Nanofluids, which are liquids with engineered nanometer-sized particles suspensions, have drawn remarkable attraction from the researchers because of their enormous potential to enhance the efficiency in heat-transfer fluids. In the present study, water-based calcined mesoporous silica nanofluids were prepared and characterized. The commercial mesoporous silica (MPSiO2) nanoparticles were dispersed in deionized water by means of pH adjustment and ultrasonic agitation. MPSiO2 nanoparticles were observed to have an average particle size of 350 ± 100 nm by SEM analysis. The concentration of MPSiO2 was varied between 1 and 6 wt%. The physicochemical properties of nanofluids were characterized using various techniques, such as particle size analyzer, zeta-potential meter, TEM, and FT-IR. The thermal conductivity was measured by Transient Plane Source (TPS) method, and nanofluids showed a higher thermal conductivity than the base liquid for all the tested concentrations.

  • 29.
    Nikkam, Nader
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Saleemi, Mohsin
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Toprak, M.S.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Singh, S.P.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Effect of nanoparticle morphology on thermal conductivity and rheology of Zinc Oxide nanofluids2012Conference paper (Refereed)
    Abstract [en]

    Nanofluids are stable dispersions of engineered nanometer-sized particles which have shown potential to enhance heat transfer properties. Nanoparticle morphology might influence the heat transport properties of the nanofluid. In this work our aim is to investigate the influence of nanoparticle morphology in the heat transfer and rheological properties of  ZnO nanofluids. ZnO nanoparticles and nanorods were synthesized and dispersed in ethylene glycol, as the base fluid, to obtain nanofluids with different percentages of nanoparticle loading. Ultrasonic agitation was used for obtaining a stable suspension and the use of surfactants was avoided. The concentrations of ZnO nanofluids were varied between 1 wt% and 3 wt%. The physicochemical properties of nanofluids were characterized by using various techniques including particle size analyzer, transmission electron microscopy (TEM), scanning electron microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FT-IR). The thermal conductivity of prepared nanofluids were measured by Transient Hot Wire (THW) method and our finding on the physicochemical, transport and rheological properties of the ZnO nanofluids, containing nanoparticles with different morphology, are presented in detail.

  • 30.
    Nikkam, Nader
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Saleemi, Mohsin
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Toprak, Muhammet
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Nano-engineered SiC Heat Transfer Fluids for Effective Cooling2013Conference paper (Refereed)
  • 31.
    Nikkam, Nader
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Saleemi, Mohsin
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Toprak, Muhammet
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Bitaraf Haghighi, Ehsan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Palm, Björn
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Microwave-assisted Synthesis of Copper Nanofluids for Heat Transfer Applications2011Conference paper (Refereed)
  • 32.
    Nikkam, Nader
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Saleemi, Mohsin
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Toprak, Muhammet
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Haghighi, E.B.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Khodabandeh, R.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Palm, B,
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Rheological Properties of Copper Nanofluids Synthesised by Using Microwave-Assisted Method2012In: Proceedings of the 4th International Conference on Nanostructures (ICNS4), 2012, p. 1555-1557Conference paper (Refereed)
  • 33.
    Nikkam, Nader
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Singh, Sathya Prakash
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Saleemi, Mohsin
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Toprak, Muhammet
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    A comparative study of rheological properties and thermal conductivity of silver nanofluids in water and ethylene glycol base fluids2012Conference paper (Refereed)
  • 34.
    Nikkam, Nader
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Toprak, Muhammet S.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Tailoring thermo-physical properties of water/ethylene glycol based nanofluids by composite SiC/SiO2 nanoparticles2015Conference paper (Refereed)
    Abstract [en]

    Conventional fluids, such as water (W), ethylene glycol (EG) and mixture of them (W/EG), are usually used as heat transfer fluids. Their poor heat transfer rate is an obstacle for enhancing efficiency of heat exchangers. A novel type of fluids called “nanofluids” (NFs) is recognized for improving the performance of heat transfer fluids. NFs are two phase fluids where solid nanoparticles (NPs) are dispersed in base liquids, which are expected to enhance the heat transfer properties of traditional fluids by improving their thermal conductivity (TC). In the last decade, NFs have achieved considerable attention due to their enhanced thermal conductivity. Mainly two methods are used to fabricate NFs: the two-step method wherein first NPs are synthesized and then dispersed in the conventional heat transfer fluids, while in the one-step method NPs are formed directly inside the base liquid. Due to large scale availability of commercial NPs, two-step method is the most commonly used technique. However, some issues such as presence of impurities or undesired phase on commercial NPs may influence the thermo-physical properties of NFs including TC and viscosity. In fact, making commercial NPs without any impurities is almost impossible and removal of undesired phases from the commercial NPs with no negative impact on NPs composition is also difficult. Hence, to study the real contribution of NPs on thermo-physical properties of NFs we performed a systematic experimental work using commercial SiC NPs with both α- and β crystal structure and silica (SiO2) NPs as secondary phase to make SiC/SiO2 composite material. The reason for selecting SiO2 is due to our recent findings on commercial α- and β SiC NPs where analysis on NPs, particularly β phase, showed silica impurity phase. Presence of this impurity/undesired phase does not reflect the real heat transport property of SiC NPs. Thus we focused on fabrication of SiC/ SiO2 composite material with different structures including core-shell structure (presence of silica phase as shell), functionalization of SiC NPs with SiO2 phase as well as addition of different percentage of SiO2 to SiC NPs as secondary phase. The obtained composite materials were used to fabricate W/EG based NFs with 9wt% NP concentration. Physicochemical properties of NPs/NFs were characterized by using various techniques. The thermo-physical properties of NFs including TC and viscosity were measured and analyzed at 20 oC. Our findings and results obtained from physico-chemical, thermo-physical and heat transport characteristics are presented in detail.

  • 35.
    Saleemi, Mohsin
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Ghadami Yazdi, Milad
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Toprak, Muhammet
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Effect of particles size and surface modification on thermal conductivity and viscosity of alumina nanofluids2013Conference paper (Refereed)
    Abstract [en]

    Electronics industry growing faster and it demands ultrahigh performance cooling systems to manage the heat loses in terms of energy and money. Conventional cooling fluids are approaching to its limit due to the poor thermal transport performance and a new era for the heat transfer fluids had been initiated about two decades ago. When nanoparticles dispersed in conventional heat transfer fluid (like water, oil, glycols), the mixture is called as nanofluids. Alumina suspensions are well known class of nanofluids, which have been investigated in many recent studies to determine the non-classical behavior of the suspensions. The aim of this study is to investigate optimized particle size and suitable surface modification for the improved dispersion properties of nanofluids with enhanced thermal performance and low viscosity. We have utilized two different types of alumina crystal phases; one is Boehmite (γ-AlOOH) and clay type (α -Al2O3) and the nanofluids were prepare d by suspending different size of nanoparticles in water and water/ethylene glycol (EG) mixtures. Dynamic light scattering (DLS) was used to determine the agglomerate size and scanning electron microscope (SEM) used to study the particle size and morphology. Zeta potential was measured to determine the electrostatic stability for the dispersed nanoparticles. Thermal conductivity was estimated by using KD2 Pro setup and up to 10 % enhancement in TC was observed as compared to the base fluid. Viscosity was measured by capillary viscometer, which shows the significant effect from the addition of additives and surfactants. Possible mechanisms contributing in reducing the viscosity and increasing the thermal conductivity are described in details.

  • 36.
    Saleemi, Mohsin
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Muhammad, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Toprak, Muhammet
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Aging, Thermal Cycling and Stability Studies for Nanofluids2015In: Aging, Thermal Cycling and Stability Studies for Nanofluids, 2015Conference paper (Refereed)
    Abstract [en]

    Stability of nanofluids is one of the critical assessments for the efficient systems that the solid content of nanofluid should be stable and well dispersed for longer time. Production of a homogenous dispersion is real technical challenge due to strong van der Waals attraction among the nanoparticles, which preferring the formation of aggregates. Stable nanofluids can be achieved via recommended physical and chemical treatments such as addition of additives and surfactants, surface-active agents to disperse hydrophobic materials, adjusting the pH value to provide electrochemical stability.Detailed investigations were carried out to identify the stability parameters, dispersion methods, application requirements, experimental investigation to determine the stability of nanofluids. Aluminum oxide (Al2O3), titanium oxide (TiO2) and cerium oxide (CeO2) were selected for these studies. Custom designed stability measurement setup was used to record the sedimentation rate. Aging test was performed in the heat transfer coefficient (HTC) setup to determine the erosion and corrosion properties. Thermal cycling was performed up to 80 oC with maximum heating cycles of 500 times. Dynamic light scattering (DLS) used to estimate the aggregate size before and after the thermal cycling and aging test. Results from the time depended DLS measurements, sedimentation rate and aging effects presents that Al2O3 nanofluids have better performance.

  • 37.
    Saleemi, Mohsin
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Toprak, Muhammet
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    One Step synthesis of Ceria (CeO2) Nanofluids with enhanced thermal transport Properties2011In: NanoTR VII: 7th Nanoscience and Nanotechnology Conference, 2011Conference paper (Refereed)
  • 38.
    Saleemi, Mohsin
    et al.
    KTH, School of Information and Communication Technology (ICT), Material Physics (Closed 20120101), Functional Materials, FNM (Closed 20120101).
    Toprak, Muhammet
    KTH, School of Information and Communication Technology (ICT), Material Physics (Closed 20120101), Functional Materials, FNM (Closed 20120101).
    Li, Shanghua
    KTH, School of Information and Communication Technology (ICT), Material Physics (Closed 20120101), Functional Materials, FNM (Closed 20120101).
    Ma, Ying
    KTH, School of Information and Communication Technology (ICT), Material Physics (Closed 20120101), Functional Materials, FNM (Closed 20120101).
    Wang, Xiaodi
    KTH, School of Information and Communication Technology (ICT), Material Physics (Closed 20120101), Functional Materials, FNM (Closed 20120101).
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Material Physics (Closed 20120101), Functional Materials, FNM (Closed 20120101).
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Material Physics (Closed 20120101), Functional Materials, FNM (Closed 20120101).
    Haghighi, Ehsan Bitaraf
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Palm, Björn
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Ceria Nanofluids for Efficient Heat Management2010Conference paper (Refereed)
  • 39.
    Saleemi, Mohsin
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM. Stockholm University, Sweden.
    Vanapalli, S.
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Toprak, Muhammet S.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics.
    Classical Behavior of Alumina (Al2O3) Nanofluids in Antifrogen N with Experimental Evidence2015In: Journal of Nanomaterials, ISSN 1687-4110, E-ISSN 1687-4129, Vol. 2015, article id 256479Article in journal (Refereed)
    Abstract [en]

    A nanofluid is a suspension containing nanoparticles in conventional heat transfer fluids. This paper reports on an investigation of alumina (Al2O3) nanoparticles in Antifrogen N, also called AFN, which is a popular antifreeze coolant consisting primarily of ethylene glycol and other additives to impede corrosion. The base carrier fluid is 50% by weight of water and 50% by weight of AFN. We systematically measured the nanomaterials and heat transfer data of nanofluids for four different size particles, namely, 20, 40, 150, and 250 nm alumina particles. The pH of all the nanofluids is adjusted to have a stable dispersion. The material characterizations include SEM and DLS particle measurements. We measured thermal conductivity, viscosity, and heat transfer coefficient in developing flow of the nanofluids. We observed that these nanofluids behave as any other classical fluids in thermally developing flow and classical heat transfer correlations can be used to completely describe the characteristics of these nanofluids.

  • 40.
    Singh, Sathya P.
    et al.
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Nikkam, Nader
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Ghanbarpour, Morteza
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Toprak, Muhammet
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Khodabandeh, Rahmatollah
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Design and Evaluation of Carbon Nanotube Based Nanofluids for Heat Transfer Applications2013In: MRS Spring 2013 Proceedings: Symposium on Nanoscale Heat Transport—From Fundamentals to Devices, Materials Research Society, 2013Conference paper (Refereed)
    Abstract [en]

    The present work investigates the fabrication, thermal conductivity (TC) and rheological properties of water based carbon nanotubes (CNTs) nanofluids (NFs) prepared using a two-step method. As-received (AR) CNTs heated and the effect of heat treatment was studied using X-ray diffraction and thermogravimetric analysis. The AR-CNTs and heat-treated CNTs (HT-CNTs) were dispersed with varying concentration of surface modifiers Gum Arabic (GA) and TritonX-100 (TX) respectively. It was found that heat treatment of CNTs effectively improved the TC and influenced rheological properties of NFs. Scanning electron microscopy analysis revealed TX modified NFs showed better dispersion ability compared to GA. Surface modification of the CNTs was confirmed by Fourier Transformation Infrared (FTIR) analysis. Zeta potential measurement showed the stability region for GA modified NFs in the pH range of 5-11, whereas pH was between 9.5-10 for TX NFs. The concentration of surface modifier plays an extensive role on both TC and rheological behavior of NFs. A maximum TC enhancement of 10% with increases in viscosity around 2% for TX based HT-CNTs NFs was measured. Finally comparison of experimental TC results with the predicted values obtained from a model demonstrated inadequacy of the predictive model for CNT NFs system.

1 - 40 of 40
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